1. Field of the Invention
The present invention relates to an adapter for an electric appliance, and more particularly to an electric adapter with display unit mounted on the adapter, capable of displaying various electrical parameters of the electric appliance.
2. Description of the Prior Art
Conventionally, a specific electronic measuring instrument is used to measure a quantity or variable of an electric appliance in order to know the electrical parameter of the electric appliance.
For example, a commercial voltmeter or volt-ohm-millimeter is generally used to measure the voltage value of an electric socket. Typically, the voltmeter is provided with a scale selecting switch. To measure the voltage level, a proper AC voltage scale must be selected by operating the scale selecting switch, and then a positive testing probe and a negative testing probe plugged into the voltmeter must be carefully inserted into the sockets respectively for performing the voltage measurement. Again for example, when it is desired to know the current passing through an electric appliance, such as a rice cooker, an ampere-meter or a hook type amperemeter is used to measure the current flow. Such measuring operation can be performed only by those skilled in electric field. For ordinary users or nonprofessional persons, such work can be hardly done.
Furthermore, it will be more difficult for ordinary users to measure the electrical parameters such as kilowatt-hour, power factor, watt, etc. of the electric appliances.
Thus, it is desirable to provide an improved electric adapter with a display unit which is capable of indicating various electrical parameters of an electric appliance.